The document DE 10 2008 037 356 illustrates a system for testing tyres for the purpose of quality check and for reducing the risks tied to safety. Such tests allow the recognition of defective points. The system comprises a reader device for reading an identifier adapted to identify the tyre, a transport system provided with a plurality of transport sections for conveying the tyres along a transport direction, at least one test device and at least one check device adapted to check the reader device, the transport system and the test device. The transport system is provided with a plurality of sensors which detect the presence of a tyre in the transport sections. The check device is configured for recording the position of the tyre in the transport sections and for keeping track of the movement of the tyre itself. In one embodiment of such document, two test devices are illustrated, arranged in sequence and intended to test the tyres by means of different measurement methods.
The document EP 1 436 789 illustrates a method and a device for inspecting a tyre. The tyre to be inspected is first associated with a rim formed by two portions and inflated in an assembly station, then brought in sequence into multiple inspection stations where the tyre is made to rotate together with the rim while the inspection operations are executed, and then the tyre is brought into a disassembly station where the tyre is deflated and the portions of the rim are removed therefrom.
The document US 2012/0134656 illustrates an illumination device and an inspection device for a tyre which are capable of detecting irregularities in the shape of the tyre itself. A photographic device photographs the inner surface of the tyre while a guide device makes the tyre and the inspection device rotate with respect to each other around an axis of the tyre. Meanwhile, a light unit arranged along the peripheral inner surface of the tyre emits light in a circumferential direction of the tyre itself. One embodiment of such document illustrates three successive, side-by-side inspection portions into which a tyre is brought in sequence by means of transport portions. The tyre lying in the first inspection portion is moved onto the rotary table of the second inspection portion, the tyre lying in the second inspection portion is moved onto the rotary table of the third inspection portion and the tyre lying in the third inspection portion is moved onto an outlet table.
In the context of automated systems for the inspection of the tyres that exit from the production line, like those described above, the Applicant has observed that the time actually necessary for a complete and careful check of each single tyre is not technically compatible with the high productivity of the current production lines (building and vulcanisation). In current plants, this signifies checking all the tyres produced but foregoing part of the numerous checks or, alternatively, executing careful checks only on some tyres (random checks).
In particular, the Applicant has observed that the known systems are not able to execute a careful check of all the tyres in the times set by the building/production line, i.e. executing such checks in line without the tyres to be checked being accumulated.
The Applicant has also verified that the known automated systems are in some cases very bulky (see for example the document DE 10 2008 037 356), in other cases structurally complex and hence costly and not very reliable (like those described in documents US 2012/0134656 and EP 1 436 789).